A dialog or a modal is a window overlaid on the primary window. It interrupts the user and requires an action. It disables the main content until the user explicitly interacts with the modal dialog. Windows under a modal dialog are inert: users cannot interact with content outside an active dialog window. Inert content outside an active dialog is visually obscured or screened. Because a dialog is highly disruptive to the user, it should be used sparingly, only when user’s interaction is required to continue.
- Content requires full attention.
- For important warnings, as a way to prevent or correct critical errors.
- Requesting a simple but critical action, like saving changes, necessary to the current process.
- Providing supplemental tasks required by the underlying page.
Don’t use when
- Providing non-essential information related to the underlying page.
- Interrupting high-stake processes such as checkout flows.
- Conveying brief thoughts or status changes. Instead, use an Alert. Toast, or Message, depending on priority.
- Complex decision-making is needed by the user that requires additional sources of information unavailable in the modal.
- The modal content can be incorporated into the underlying page without complicating the page’s intent.